Buggy code:
public abstract class AbstractClassDiagramProfileImpl extends AbstractEmfDiagramProfile { public static final String CMMNTYPES_PATHMAP = "pathmap:////jbpm-cmmn//libraries//cmmntypes.uml" ; private static final String STENCILSET_PATH = "stencilsets//ucd//ucd.json" ; static Logger LOGGER = LoggerFactory . getLogger ( AbstractClassDiagramProfileImpl . class ) ; @ Inject private DataModelerService dataModelerService ; @ Inject private KieProjectService projectService ; @ Inject RepositoryDescriptor repositoryDescriptor ; @ Inject Instance < HttpServletRequest > request ; @ Inject @ ProfileName ( "ucd" ) ClassDiagramFormBuilder classDiagramFormBuilder ; public AbstractClassDiagramProfileImpl ( ) { } @ Override public IEmfBasedFormBuilder getFormBuilder ( ) { } public String getTitle ( ) { } public String getName ( ) { } public String getStencilSetNamespaceURL ( ) { } public void prepareResourceSet ( ResourceSet resourceSet ) { } @ Override public Map < String , Object > buildDefaultResourceOptions ( ) { } public static Package getCmmnTypes ( ResourceSet resourceSet ) { } private static URL mapClassPathResource ( ResourceSet resourceSet , URI uri , String resourcePath ) { URL url = UMLDiagram . class . getResource ( resourcePath ) ; String externalForm = url . toExternalForm ( ) ; try { InputStream openStream = url . openStream ( ) ; Field this$0 = openStream . getClass ( ) . getDeclaredField ( "this$0" ) ; this$0 . setAccessible ( true ) ; ZipFile zf = ( ( ZipFile ) ( this$0 . get ( openStream ) ) ) ; String jarUri = ( ( "jar:file:" + ( zf . getName ( ) ) ) + "!" ) + resourcePath ; externalForm = new URL ( jarUri ) . toExternalForm ( ) ; } catch ( Throwable t ) { AbstractClassDiagramProfileImpl . LOGGER . warn ( "Could<seq2seq4repair_space>not<seq2seq4repair_space>calculate<seq2seq4repair_space>jar<seq2seq4repair_space>file<seq2seq4repair_space>path" , t ) ; } URI cmmnTypesUri = null ; if ( externalForm . contains ( "vfs://" ) ) { if ( ( externalForm . lastIndexOf ( ".jar//" ) ) > 0 ) { cmmnTypesUri = URI . createURI ( externalForm . replace ( "jar:" , "archive:" ) . replace ( "vfs:" , "archive:file:" ) . replace ( ".jar//" , ".jar!//" ) ) ; } else { cmmnTypesUri = URI . createURI ( externalForm . replace ( "vfs:" , "file:" ) ) ; } } else { <START_BUG> cmmnTypesUri = URI . createURI ( externalForm ) ; <END_BUG> } resourceSet . getURIConverter ( ) . getURIMap ( ) . put ( uri , cmmnTypesUri ) ; String [ ] languages = new String [ ] { "java" , "js" } ; for ( String l : languages ) { resourceSet . getURIConverter ( ) . getURIMap ( ) . put ( AbstractClassDiagramProfileImpl . mappingsUriForLanguage ( uri , l ) , AbstractClassDiagramProfileImpl . mappingsUriForLanguage ( cmmnTypesUri , l ) ) ; } return url ; } private static URI mappingsUriForLanguage ( URI uri , String l ) { } @ Override public Factory getResourceFactory ( ) { } @ Override public EmfToJsonHelper createEmfToJsonHelper ( ShapeMap resource ) { } @ Override public IDiagramMarshaller createMarshaller ( URI uri ) { } private void generateDataModel ( XMLResource r ) { } @ Override public JsonToEmfHelper createJsonToEmfHelper ( ShapeMap resource ) { } @ Override public String getStencilSetPath ( ) { } @ Override protected ResourceTypeDefinition getResourceTypeDefinition ( ) { } @ Override public String getDiagramStencilId ( ) { } @ Override public boolean useIdAttribute ( ) { } @ Override public String getProfileDefinitionFileName ( ) { } @ Override protected void populateModelStub ( XMLResource rs ) { } @ Override public EPackage [ ] getEPackages ( ) { } @ Override public String getFormId ( XMLResource resource , String classId , String formType ) { } }

Fix:
cmmnTypesUri = URI . createURI ( externalForm . replace ( "jar:" , "archive:" ) ) ;